利用氟化氪準分子雷射重整系統製備高相容性低損耗矽光波導結構

Abstract

光學於短矩離資料傳輸是一個可靠，有希望的替代方式。在這裡，我們利用準分子雷射重整系統研發新進的製程方法製備高相容性且低損耗的矽光波導結構。這個研究解決了製作光子元件與電子元件於同一晶片上的整合問題，同時有效降低光波導的傳輸損耗。利用形貌調變的方式，我們直接製單晶矽波導結構於一般的純矽基板上。這個方法克服了矽光子元件必須使用絕緣層上矽平台的限制。它代表了一個製作可靠的矽波導結構於半導體製程相容的純矽基板的方法，同時顯示整合光子元件與電子元件於同一晶片的潛力。此外，我們利用準分子雷射系統解決了由於蝕刻所造成的側表面粗糙的問題。在適合的雷射能量下，傳輸損耗從原本的4.2 ± 0.2 dB/cm降到 2 ± 0.2 dB/cm。另一方面，我們利用準分子雷射製作次微米矽球結構。這個結構具有超高質量因子的迴音壁模態，適合於各式的光子元件應用。

Optics is a promising alternative for short-reach data interconnections. In this work, the fabrication method of CMOS-compatible low-loss Si waveguiding structures by KrF Excimer laser reformation system is studied. The study solves the on-chip integration issues between electronics and photonics, as well as reduces the propagation loss for on-chip optical interconnect applications. Crystalline Si waveguides on a pure Si substrate by using a profile modification method is demonstrated for the first time. It overcomes the limitation of using a SOI platform in Si photonics. This represents a viable method to create reliable Si waveguides on CMOS-compatible Si substrate and shows the potential of Si photonic devices when they are integrated with Si electronics. In addition, sidewall smoothing for silicon ridge waveguides is presented. Propagation loss is measured using grating couplers and spiral samples. Under proper laser treatment, the propagation losses are reduced from 4.2 ± 0.2 dB/cm to 2 ± 0.2 dB/cm. It shows at least 50% loss reduction. Furthermore, the fabrication of sub-micron Si spheres is presented. The Si spheres have mono-crystalline property and ultra-smooth surface. It supports the whispering gallery modes with ultra-high quality-factor and is suitable for various photonic applications.